In a long term evolution architecture, one technology being utilized is adaptive modulation and coding (AMC). AMC allows the modulation scheme and coding to be changed on a per-user basis depending on signal quality and cell usage.
To facilitate AMC operations, in LTE, the user equipment (UE) is required to periodically report the channel quality indication (CQI), for example every two milliseconds. The CQI feedback for AMC incurs significant overhead to both the uplink channel and the UE's battery power due to the continuous CQI transmission.
Further, data traffic is often bursty and a UE could be idle for a significant portion of time for which during which CQI feedback is ongoing.